1. Field of the Invention
The present invention relates to a process and system for converting thermal energy from moderately low temperature sources, especially from geothermal fluids, into mechanical and/or electrical energy.
More particularly, the present invention relates to a process and system for converting thermal energy from moderately low temperature sources, especially from geothermal fluids, into mechanical and/or electrical energy including high pressure and low pressure circuits, where all partially condensed liquid from the high pressure circuit is combined with the stream coming from the low pressure circuit forming a lean stream which can be condensed at a pressure lower than a pressure required to condense the stream had its composition not been made lean or its concentration lowered.
2. Description of the Related Art
Prior art methods and systems for converting heat into useful energy at well documented in the art. In fact, many such methods and systems have been invented and patented by the inventor. These prior art systems include U.S. Pat. Nos. 4,346,561, 4,489,563, 4,548,043, 4,586,340, 4,604,867,4,674,285,4,732,005,4,763,480,4,899,545,4,982,568,5,029,444, 5,095,708,5,440,882, 5,450,821, 5,572,871, 5,588,298, 5,603,218, 5,649,426, 5,822,990, 5,950,433 and 5,593,918; Foreign References:7-9481 JP and Journal References: NEDO Brochure, “ECO-Energy City Project”, 1994 and NEDO Report published 1996, pp. 4-6,4-7,4-43,4-63,4-53, incorporated herein by reference.
Although all of these prior art systems and methods relate to the conversion of thermal energy into other more useful forms of energy from moderately low temperature sources, all suffer from certain inefficiencies. Thus, there is a need in the art for an improved system and method for converting thermal energy from moderately low temperature sources to more useful forms of energy, especially for converting geothermal energy from moderately low temperature geothermal streams into more useful forms of energy.